Improvement in keys



UNITED STATES PATENT OFFICE.

THOMAS S. BOWMAN, OF ST. LOUIS, MISSOURI.

IMPROVEMENT IN KEYS.

Specification forming part of Letters Patent No. 54,678., dated May 15,1866.

To all whom it may concern- Be it known that I, THOMAS S.BOWMAN, of St.Louis, in the county of St. Louis and State Missouri, have invented anew and useful Improvement in Keys; and I do hereby declare that thefollowing is a full, clear, and exact description thereof, which willenable those skilled in the art to make and use the same, referencebeing had to the accompanying d rawings, forming part of thisspecification, in which Figure l is a longitudinal section of a lockkeywith my improvement applied to it. Fig. 2 is also a longitudinal sectionof the same applied to a lock.

Similar letters of reference indicate corresponding parts.

This invention relates to a new and useful improvement in keys forlocks, watches, and all keys in which the shanks-or arbors are drilledlongitudinally to work on a pin when in use or applied to their work.Keys of this description, especially those which are carried in thepocket, are liable to have their holes filled up with dirt, lint,&c.,and frequentlymuch trouble and inconvenience are experienced inpicking the dirt or lint out of the hole before the key can be applied.

My invention is designed to obviate this difficulty, and to this end Ihave the hole drilled rather deeper or donger than usual into the shankor arbor of the key, and insert a spiral spring thereinhaving a buttonor disk' attached to its outer end to fill the hole or serve as astopper for the same, the spring keeping the stopper at the orifice ofthe hole and preventing the admission of dirt, but readily yieldingunder pressure when the .key isapplied,

ner end of. the hole, so as not tointerfere at all with the readyapplication of the key to its work or the turning of it upon its pin,the stopper, when the key is withdrawn, being instantly forced back tothe orifice of the hole in the shank or arbor.

A represents an ordinary lock-key having a hole, a, drilled in its shankor arbor b to fit on a pin, 0, in thelock, the key turning on said pinin looking or unlocking the lock.

B represents a spiral spring, one end of which has a bar, (I, attachedto it of such a length that when the spring B is forced into the hole ait will bind in said hole and prevent the spring from slipping out fromit.

At the outer or opposite end of the spring there is secured a button orstopper, 0, of such diameter that it will fill the hole a, but stillslide freely therein the spring B, when not acted upon or subjected toany pressure, keeping the disk or stopper 0 at the orifice of the holea, as shown in Fig. 1. This stopper, it will be seen, will effectuallyprevent the admission of dirt and lint into the hole of the shank orarbor of the key, while it will not in the least interfere with theapplication of the key to its work, as the springB readily yields and iscompressed as the key is shoved forward on its pin. Thus by this simpledevice the hole a in the shank or arbor of the key may be kept perfectlyfree from dirt, and the annoyance alluded to avoided.

1 Having thus described my invention, I claim as new and desire tosecure by Letters Pat

